1. Field of the Invention
The present invention relates to a waterproof sheet for concrete structures.
2. Description of the Prior Art
The conventional waterproof sheet adhered to the surface of a concrete structure with use of an adhesive is liable to be damaged when the concrete structure becomes cracked.
To solve the problem set forth above, the applicants proposed a waterproof sheet for an engineering and construction structure as disclosed in Japanese Patent Publication No. 46-35337. This waterproof sheet is illustrated in FIG. 4 and comprises a sheet made of a thermoplastic synthetic resin and a filament, such as asbestos, glass, polyamide, etc., or powder, such as pumice, vermiculite, slag, glass, etc. The filament or powder is partially embedded into and adhered to the waterproof sheet with a slight interval being provided between the filament or powder and the waterproof sheet. This proposed waterproof sheet does not have the problem that arises in the conventional waterproof sheet employing adhesives. However, there arises the problem that the waterproof sheet is not always adhered to the surface of the concrete structure uniformly and integrally since the proposed waterproof sheet was adhered physically thereto with the filament or powder therebetween.